Yes. It even has implemented some of the extra
functionality mentioned in the RFC. See the
RFC Compliance section for complete list.

4.2. Can I mix site-local and global IPv6 addresses?

Yes. But keep in mind that they intentionally were not
designed to be used at the same time. The network topology can be
quite "messy" if you start using these two.

4.3. The GUI front-end failed to compile...why?

You probably don't have the GTK2.0 development libraries
installed.

4.4. If there is multiply gateways present, how does
the mobile node conclude to use the nearest one?

When a new gateway is detected, the Mobile Node checks the
distance (number of hops) to this newly discovered gateway
compared to the current gateway. If there is a shorter distance,
this new gateway becomes the current (default) gateway. See
section 12.6.2 in the OLSR RFC (RFC3626)

4.5. I get OLSRd up and running - but the nodes
don't seem to "hear" each other!

Most of the time this is a configuration error: Check
the following:

If using WLAN interfaces make sure the ESSID/key match.

Make sure the cards are set in "ad-hoc" mode
and not "managed".

Make sure you are not blocking UDP/698. If using
netfilter run ip6tables -L as root
to see what rules are set. ip6tables
-F flushes all rules.